May 24, 2017
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Quick News & Press Release
GENOA 4.4 Released
NANO Capability Introduced
New PFA Unit Cell
New MCO Unit Cell
Issue #22 - 7/16/2013
Structural Health Monitoring Test Validation
Issue #21 - 1/16/2013
Managing Defects & End of Life Prediction / Validation in Composite Wind Turbine Blades
Issue #20 - 4/13/2010
Material Characterization & Qualification (MCQ)
Issue #19 - 11/17/2009
Composite Structures & Parametric Robust Design (PRD)
Issue #18 - 7/13/2009
Numerical Approach to Determine Crack Path and Delamination Growth in Composite Structures
Issue #17 - 5/4/2009
Certification-by-Analysis (CBA)
Issue #16 - 10/20/2008
Material Qualification and Certification Determine Allowables by Means of Virtual Simulation Combined With Limited Testing
Issue #15 - 6/10/2008
Predicting Post-Buckling Response and Ultimate Failure of Composite 2-Stringer Panels
Issue #14 - 4/28/2008
Composite Storage Module Joint Analysis and Test Verification
Issue #13 - 2/25/2008
GENOA 4.3 Release with A- and B-Basis Allowables
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A- & B-Basis Allowables

A-& B-Basis Allowables (AB_ALLOWABLE)

View Product Datasheet (PDF)


Accurate prediction of A-basis and B-basis strength values is critical to reduce risk in structural design of aircraft structures made from composite material. This GENOA module effectively reduces the number of coupon testing by simulating the scatter in composite material properties and fabrication parameters. There are three distinct capabilities (options) available for users of this GENAO module:

·         Option 1 using user provided test data: Predict A and B basis strength values using user provided test data. This capability complies with standards and recommendations from MIL HDBK 17E: Military Handbook for Polymer Matrix Composites and FAA CFR 14 Aeronautics and Space. This option does not involve progressive failure analysis. It is purely based on user supplied test data.

·         Option 2 using virtual simulation combined with limited test data:  Predicts A and B basis strength values by reproducing scatter from limited tests (one coupon strength value from each cure cycle of each batch is recommended as input). This capability produces the scatter from few tests supplied by the user by applying uncertainties on fundamental primitive variables of constituent fiber and matrix properties and composite fabrication parameter. User can iterate on coefficient of variation of the random variables to collectively reproduce the scatter in the test. This analysis option combines progressive failure analysis (FEA based) or PFA Unit Cell with probabilistic method to fit the scatter from the test. The PFA Unit Cell allowables capability can be applied to any un-notched coupon producing allowables strength values in few minutes. On the other hand, the PFA based allowables can be applied to any ASTM type test or any structural component level.  A by-product of this analysis is the sensitivity information which ranks the influence of the random variables on the material strength.

·         Option 3 virtual simulation without test data:  Estimates A and B basis strength values by virtual generation of scattered strength for coupon or structural component. The code generates strength response by perturbing material fiber/matrix/interface/ply properties and/or composite fabrication variables using user provided coefficient of variation. The analysis process relies on PFA to collect final strength data for perturbed random variables (above and below the mean) to simulate coupon test behavior. Once the various strength data are collected, the data are passed to option 1 again as if they were real test data to assess A and B basis values using Mil HDBK procedures.  This capability is very effective when no test data are available and can be used as a guide to material selection.   


·         Effective tool to reduce risk in structural design.

·         Reduces the number of coupon tests needed for material qualification.

·         Accelerates material qualification for certification.

·         Provides a guideline to material selection when no test data are available.

·         Evaluates scatter in material strength.

·         Applicable to all types of material architectures, all types of ASTM tests, and all levels of structural components.

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